REPLACEMENT GEARBOXES and GEARS available from Loco Doc

GEARBOXES FOR 3MM AXLES (USED ON ALMOST ALL HO BRASS)  
BRAND PSC PSC PSC PSC NWSL NWSL NWSL NWSL NWSL NWSL NWSL NWSL
PART #  4018  4018.1 4018.13 4018.12  140-6  139-6  136-6  151-6  150-6  241-6  240-6  170-6
Gear Size  72DB  72DB  72DB  72DB  3MOD  3MOD  3MOD  3MOD  3MOD  72DB  72DB  3MOD
RATIO    27/1    36/1    27/1    27/1    27/1    27/1    27/1    36/1    36/1    28/1    28/1    50/1
# of Idlers      1      1       0        1        0       1       2        0       1       0       1       1
Worm Offset   .775"   .860"   .310"   .710"   .256"   .591"   .925"   .303"   .732"   .323"    .78"   .365"
CASE METAL MET PLAST PLAS PLAS PLAS PLAS PLAS PLAS PLAS PLAS PLAS
MinWheel" 49-40" 62-54" 40-30" 40-30" 46-33" 46-33" 40-33" 56-40" 56-40" 58-43" 58-43" 33-28"
Options A,C B W N,X Q,W P,W P,X Q,W Q,X Z
PRICE $38.50 $17.25 $12.25 $16.50 $24.95 $29.95 $31.95 $24.95 $29.95 $24.95 $29.95 $34.95
        Minimum Driver Diameter; First # is with gearbox cover, Second # is with gear exposed.
OPTIONS;
A. This gearbox was recently replaced by a BO RIM produced box with a bracket for a trailaing arm
        and about a .70" worm offset. I have a few of the earlier style box available.
B. A similar pair of gearboxes for articulateds as a "high low" gearbox set is #4018.6 at $39.75.
C. A similar pair of gearboxes for articulateds as a "high-low" gearbox set is #4018.14 at $39.75.
N. Available for articulateds as a "high-low" gearbox set as #188-6  $37.95
P. Available for articulateds as a "high-low" gearbox set as#158-6  $39.95
Q. Available for articulateds as a "high-low" gearbox set as#247-6  $39.95
W.Convertable to 2mm worm shaft (part # 144-6 ), for 1.5mm worm shaft order part #145-6 Price for either  $6.00
X. Convertable to 2mm worm shaft (part #164-6), for 1.5mm worm shaft order part #165-6 price for either  $6.00
Z. 2.4mm driver axle. gearbox #171-6 for 2mm axle,#172-6 for 1.5mm axle and #173-6 for 3mm axle, wheels
        must be installed on 3mm brass axle which is integral with gear.
COMMENTS;
        The PSC gearboxes are my current favorite because they have spherical bronze worm shaft bearings and assemble easily. Recent production of #4018 and #4018.1 (painted black) are Korean made and not the same or as good as the older KTM made boxes (silver metal color) of Westside days. I will buy any of the old ones.
        When building the NWSL gearboxes it is important for the worm shaft bearings to be perfectly inline, if not the bearings will bind on the shaft and overload the motor. When I assemble NWSL gearboxes, I chamfer the inner and outer surfaces of the gearbox halves where they touch the wormshaft bearings. Thus only a small ring of the gearbox clamps the bearing and the bearings can allign themselves on the shaft allowing free and smooth rotation of the driveshaft. Newest production is trouble free.

POLISHED STEEL WORMS TO REPLACE WORN AND DEFECTIVE GEARS  
        The worm is the most easily damaged gear and will destroy the gear it drives if it has a rough tooth surface or if it is damaged. The worm MUST be made of a discimilar and harder material than the gear it drives. Poor quality, worn or soft brass worms should be replaced before they damage other gears.
          I always replace any brass worm with a NWSL polished steel worm. It is a very cheap investment in longer gear life. A Standard worm has threads running like a screw or bolt and runs foreward turning clockwise. A reverse worm is opposite.
          The worm gear pitch (tooth size) and cut (direction) must be matched to the gears it will mesh with and the shaft hole matched to the motor shaft.

      REPLACEMENT STEEL WORMS
DESCRIPTION      NWSL          NWSL          NWSL          NWSL          NWSL          NWSL    
GEAR PITCH       3MOD       3MOD 72DP-3.5MOD 72DP-3.5MOD     4MOD       4MOD
GEAR CUT STD.WORM REV.WORM STD.WORM REV.WORM STD.WORM REV.WORM
GEAR O.D.      5MM      5MM     4.8MM     4.8MM     6MM     6MM
1.2MM SHAFT 10800-6x + 10801-6 + 50800-6 +
1.5MM SHAFT 1313-6 ^ 1335-6 ^ 10400-6 x 10401-6 x
2.OMM SHAFT 1312-6 ^ 1334-6 ^ 10500-6 x 10501-6 x 50500-6 +
2.4MM SHAFT 230600-6 - 230601-6 ^ 10000-6 0 10001-6 x 50600-6 - 50601-6 -
PRICES;     ( 0 ) = $5.00,     ( x ) = $5.50,     ( - ) = $6.00,     ( ^ ) = $6.50,     ( + ) = $7.00

POLISHED 2.5 MOD STEEL WORMS FOR PRECISION SCALE K-28, K-36 and K-37 (Korea)
These models had very fine tooth soft brass worms that wore out quickly. We produce 2.5 mod steel worms that will last but the worm is slightly larger in diameter so I have to modify the worm shaft bearings to get proper gear mesh. I also replace the soft steel worm shaft in K-36 and K-37 gearboxes with hardened steel motor shaft stock for longer life and reduced bearing wear. Phone to schedule shop time. Price is $60 per gearbox.

LOCODOC DELRIN IDLER GEAR UPGRADES FOR HOn3 WESTSIDE LOCOMOTIVES
                Quite a few very good HOn3 locomotives built by Nakamura were produced with a brass worm driving brass idler gears rotating on 3mm brass shafts. A rule of gear design is that the worm must be made of a harder and discimilar material than the "worm gear" it drives and the pivot shaft must be a smooth and harder material than any gear rotating on it. Many locomotives ( Lambert C&S 2-6-0 , Westside C-25, K-37, compound K-27, original slide valve K-27 and possibly others ) should have their brass idler gears replaced with delrin gears.
        If the shaft is worn or if you want a quieter, smoother and lower friction drive that provides much truer gear mesh and increases flywheel coast, LocoDoc has developed a custom NWSL made 26 tooth delrin idler gear mounted on a 1.5mm hardened steel shaft for greater stability. It also includes two custom brass bearings to fit the shaft and center the gear in the gearbox. This is a big improvement over the NWSL 305-6 gear that loosly mounts on the original large 3mm. brass pivot shaft. Since the gearboxes have different widths, please specify which model it will be installed in as the bearing widths needs to be machined to match the gearbox width.
        LocoDoc #305 delrin idler gear upgrade ( PHOTO )Specify model                                             $20

LOCODOC DELRIN IDLER GEARS FOR KEY MODELS
        Several models built by Samhongsa had brass idler gears which tend to be noisy and wear out and several rotate on brass sholdered screws, a short lived design. The following delrin idler gears are custom made by us using NWSL gear stock.
        LocoDoc C&S #22 2-6-0 ( PHOTO )                                                                                               $20
        LocoDoc C&S #58 2-8-0 (also #60, #65 & #69) ( PHOTO )                                                           $20
        LocoDoc RGS #42 2-8-0 This is a corrected (sleaved down)NWSL #2177                                      $20
        LocoDoc C&S #71 2-8-0 This is a corrected NWSL #2177 (bored out or sleaved)
          There are two versions; 3.1mm. (.122") and 1.9mm. (.74") pivot screws. Specify which.                  $20

NWSL DELRIN IDLER GEARS TO UPGRADE HOn3 LOCOMOTIVES
        NWSL #305-6 to replace brass idler gears in Nakamura made HOn3 locos                                      $6.95
        NWSL #2146 FOR WS & Balboa(2nd run) D&RGW T-12 originly made for me                           $11.95
        NWSL #2154 FOR WS WSLC #3 steel worm to replace soft brass one                                          $9.95
        NWSL #2161 FOR WS NCNG #9 but not SP#18 (with idler gear) Some have undersize hole          $9.95
        NWSL #2177 FOR Key C&S #71 and RGS #42, requires modifying the pivot hole                         $9.95

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